The present invention relates to exercise equipment and more particularly, to exercise equipment that uses a variable number of weights to resist exercise motion.
Exercise weight stacks are known in the art. Generally speaking, weights are arranged in a stack and movably mounted on at least one guide rod or rail. A selector rod is connected to a desired number of weights by a pin (or other suitable means known in the art). The selector rod and any selected weights are connected to a force receiving member by a cable (or other suitable means known in the art) which moves the weights upward in response to exercise movement.
Although exercise weight stacks are prevalent in the exercise industry, they nonetheless suffer from certain shortcomings. For example, in order to provide a large amount of weight at a reasonable cost and within a reasonable amount of space, equipment manufacturers use a small number of relatively heavy weights. As a result, the amount of weight being lifted cannot be adjusted in small increments. On the other hand, a relatively large number of lighter weights could be used in order to provide smaller increments in weight adjustment, but the resulting equipment would be relatively more expensive and/or bulky.
Attempts have been made to address the issue of incremental adjustments. One such approach involves the provision of a loose half-weight which is available for movement onto the top plate at the discretion of a user. This particular arrangement is not well suited for institutional environments because the half-weight may be lost or misused. Another prior art approach involves the provision of a half-weight (or other fractional weights), which weighs one-half the weight of each weight in the stack, and which is selectively movable from a peg on the frame onto an aligned peg on the top plate of the stack. This approach not only fails to overcome the possibility of losing the half-weight, but it also creates a balance problem during movement of the selected weights, and increases the potential for injury due to the proximity of the two pegs and their movement relative to one another. Yet another prior art approach involves the provision of a second, adjacent weight stack comprising weights which weigh a fraction of the weights in the primary weight stack. Unfortunately, this approach adds significantly to both the cost and the size of the equipment.
Yet another prior art machine with supplemental weights is disclosed in French Patent No. 2,613,237 to Louvet. The Louvet machine includes a stack of primary weights movable along a guide rod in response to exercise movement, and a stack of secondary weights movable along the guide rod and selectively stored above the stack of primary weights. The secondary weights are supported by gates which are rotatably mounted on rigid frame members and which have pegs that rotate into engagement with holes in the frame members. Each of nine secondary weights has a mass equal to one-tenth the mass of one of the primary weights. One disadvantage of the Louvet machine is that nothing prevents a user from releasing a secondary weight without grasping the weight being released. As a result, the secondary weight may be free to drop downward onto the top plate in the stack of primary weights, thereby increasing the likelihood of personal injury and/or damage to the machine. Also, each of the secondary weights is not separately supported by a respective gate. As a result, the entire stack of secondary weights may be released at one time, with or without a user holding onto to any of the secondary weights. Yet another shortcoming of the Louvet machine is that nine secondary weights are required to provide nine levels of incremental weight adjustments.
Still other prior art approaches are disclosed in Soviet Union Patent No. 1347-948-A and Japan Patent No. 10-118222. Each of these patents discloses first and second supplemental weights which are movably mounted on discrete guide rods outside the planform of the primary weight stack. The supplemental weights in the Soviet patent are pivotally mounted on respective guide rods for optional movement into the path of the primary weight stack, whereas the supplemental weights in the Japan patent are releasably secured to the top plate by a separate selector pin. A shortcoming common to both of these approaches are inadequate is the need for separate guide rods to accommodate the supplemental weights. In other words, despite all of the efforts discussed above, room for better solutions and/or improvements remains.
The present invention generally involves the provision of at least one supplemental weight for use on an exercise apparatus having a stack of weight plates movably mounted on a frame. The supplemental weight is selectively movable into and out of the path traversed by the top plate in the stack. In a first mode of operation, the supplemental weight is supported by a frame member in an inactive position, outside the path of the top plate, thereby allowing the top plate to move relative to the supplemental weight and the frame. In a second mode of operation, the supplemental weight occupies an active position, within the path of the top plate, thereby adding resistance to movement of the top plate relative to the frame.
One aspect of the present invention is to connect a handle to the supplemental weight to facilitate maneuvering of the supplemental weight between the inactive position and the active position. On some embodiments of the present invention, the handle is rigidly connected to the supplemental weight, while on other embodiments, a flexible connector is interconnected between the supplemental weight and the handle, and is routed about at least one guide on the frame. In either case, the handle and the supplemental weight may be disposed on opposite sides of a shield on the exercise apparatus, and the shield may be used to support the supplemental weight in the inactive position.
Another aspect of the present invention is to provide the supplemental weight and the top plate with complementary structures which register the supplemental weight relative to the top plate. For example, a boss on the supplemental weight may interengage a recess in the top plate when the former is disposed on top of the latter. Such structures maintain the supplemental weight in a desired position relative to the top plate, as well as the guide rods and connector associated with the top plate.
Yet another aspect of the present invention is to provide the supplemental weight in a form suitable for installation on existing equipment. For example, the supplemental weight may include complementary portions which can be secured about an intermediate portion of an elongate member, such as a weight stack guide rod or a connector extending between the top plate and a force receiving member. Also, a suitable holder may be secured to the frame to support the supplemental weight in the inactive position.
Still another aspect of the present invention is to provide supplemental weight(s) for movement along at least one weight stack guide rod and/or a connector interconnected between the top plate and a force receiving member, and to require the user to support the supplemental weight(s) during movement from an inactive position, supported by the frame above the path of the top plate, and an active position, inside the path of the top plate. This arrangement may be considered advantageous to the extent that a separate guide is not required for the supplemental weight(s), and/or the user must support the supplemental weight(s) during movement from the inactive position to the active position. With respect to supplemental weight(s) movable along the connector, such an arrangement may be considered advantageous to the extent that a low friction interface is not required between the supplemental weight(s) and the connector, and/or the supplemental weight(s) may be accessible through a longitudinally extending slot that is aligned with the selector rod. With respect to supplemental weight(s) movable along at least one weight stack guide rod, such an arrangement may be considered advantageous to the extent that the supplemental weight is constrained to travel along a more definite path, and/or the supplemental weight(s) may be fitted with the same bushings as the weight plates in the stack.
Yet another aspect of the present invention is to provide multiple supplemental weights with discrete amounts of mass, and allow the user to choose between the mass of the first weight, the mass of the second weight, and the combined mass of the two weights. For example, a half-weight and a quarter-weight may be movably mounted on respective weight stack guide rods and activated and deactivated in any order and/or combination.
The foregoing aspects of the present invention may be implemented individually and/or in various combinations. The present invention may also be implemented with different active positions for the supplemental weight, including on top of the top plate and/or supported at an intermediate point along the path of the top plate. In other words, the present invention can be used to facilitate conventional weight stack resistance together with fractionally increased weight stack resistance which remains constant throughout a range of motion and/or which varies during an exercise stroke.
On several embodiments of the present invention, the supplemental weight and the top plate cooperate to maintain a relatively large ring of space between the supplemental weight and any member extending through and/or adjacent the supplemental weight, in order to discourage contact therebetween during operation of the weight stack. In the alternative, and on certain other embodiments, the supplemental weights are movably mounted on the frame member(s) by bushings (or other suitable arrangements known in the art). Furthermore, the supplemental weights may be movably connected to dedicated flexible guides in the alternative.
The present invention may also be described in terms of various methods for positioning and/or selecting the supplemental weight(s). Many features, advantages, and/or variations of the present invention will become apparent from the more detailed description that follows.